You can stop patting yourself on the back for remembering to take a multivitamin every day, because it turns out you may be killing yourself by popping One A Day. Or maybe not? But maybe! Scientists have been wavering on whether vitamins are beneficial or a waste of money for some time now, and a new study ups the ante by suggesting they may be linked to an increased risk of death in older women.

The L.A. Timesreports that the study, led by a team at the University of Minnesota, looked at data from the Iowa Women's Health Study. In 1986, researchers began collecting information from 38,000 women who were around age 62 at the time. During the 19-year study, the women died at a higher rate if they took multivitamins, vitamin B6, folic acid, magnesium, zinc, copper, and especially iron, compared to those who didn't use supplements. The only one of the vitamins found to reduce the risk of dying was calcium.

On average, the women who took supplements had a 2.4% increased risk of dying during the course of the study. Lead author Jaakko Mursu, an epidemiologist at the University of Minnesota School of Public Health, said:

"Our study, as well as other similar studies, have provided very little evidence that commonly useddietary supplements would help to prevent chronic diseases ... We would advise people to reconsider whether they need to use supplements, and put more emphasis on a healthy diet instead."

Other experts say the finding doesn't mean you should toss all of your supplements, particularly because the researchers have no idea what the findings mean. Mursu speculated that iron may be toxic in high amounts, or that the women who took iron supplements were more likely to have some other condition that killed them. So until scientists perform more research, taking vitamins is a gamble that will either keep you healthy or hasten your demise.